This configuration can be found in several articles on this site. The one shown in the diagram is from the datasheet of the LM101 series amplifiers, but it can be implemented with other types.
We present a circuit formed by six voltage comparators. Each comparator will analyze the voltage...
This circuit can generate time base signals from 5 to 1500 Hz. We find it in a documentation about old neon...
In this circuit the CA3140, an operational amplifier, is used as a comparator with the zener diode...